The Atari Portfolio is the world's first IBM PC-compatible palmtop PC, released by Atari Corporation in June 1989.

DIP Research Ltd. based at the Surrey Research Park in Guildford, Surrey, UK developed the first MS-DOS compatible palmtop PC, the DIP Pocket PC. It was IBM PC-compatible at the BIOS level, but not at the IO port level. A prototype version was released in early 1989 as a proof of concept.

Atari became aware of this release, and saw a market opportunity. It licensed the electronics & software design from DIP, and applied its production engineering expertise to create a consumer version of the product with a new case and keyboard.

This product was marketed as the Atari Portfolio in the US & UK, and in other countries later on. In Germany, Italy, and Spain it was initially called the PC Folio due to trademark restrictions. Atari acquired the rights to the name Portfolio in Germany and Spain, but it was always called the PC Folio in Italy.

DIP continued to evolve the electronics design (including expansion modules) and all the ROM software, supplying software updates to Atari over the production cycle. Its licensing agreement enabled it to source Portfolios from Atari at a reduced cost, which it rebranded and sold as the production version of the DIP Pocket PC in the UK. Note the Atari key on the keyboard.

DIP Research also developed the Sharp PC-3000/3100, released in late 1991. The company was acquired by Phoenix Technologies in 1994.

Officially the name DIP stood for Distributed Information Processing, unofficial it was initials of the founders David Frodsham, Ian Cullimore and Peter Baldwin.

Prior to founding DIP the founders and several staff members had worked at Psion (company).